<!DOCTYPE html>
<html lang="zh">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=no">
    <meta http-equiv="X-UA-Compatible" content="ie=edge,chrome=1">
    <meta name="referrer" content="never">
    <title>帧动画</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        ul {
            list-style: none;
        }

        .box {
            position: relative;
            width: 300px;
            height: 300px;
            margin: 50px;
            border: 2px solid #f00;
            border-radius: 50%;
        }

        .line {
            position: absolute;
            top: 30px;
            left: 149px;
            width: 2px;
            height: 120px;
            background-color: #000;
            transform-origin: bottom;
            /* animation: round 60s linear; */
            animation: round 60s steps(60);
        }

        @keyframes round {
            from {
                transform: rotate(0deg);
            }
            to {
                transform: rotate(360deg);
            }
        }
    </style>
</head>
<body>
    <div class="box">
        <div class="line"></div>
    </div>

    动画中的 timing-function 可以更换为一个 steps(n)，表示为将动画分割为n个步骤执行，n为正整数。

    <!-- 作业：实现一个表，加上时分秒指针以及刻度 -->
    <script type="text/javascript">
        
    </script>
</body>
</html>